Access to file rights.dat denied

Hello, I am having a very strange problem on SourceOffsite 3.5.1 with
SourceSafe 5.0

I have 2 users: one and two. Both users can login to SourceSafe with no
problems. On the same machine, one user can login to SourceOffsite, user two
cannot! He gets the following error in the GUI:

The server was unable to connecto to the sourcesafe database
Please verify that sourcesafe was properly installed on the server machine

The log fiel has the following:

Tue Feb 03 12:47:52 PST 2004 - PDC (10.10.10.29) - Access to file
"\\server\drvsrv\drvsrv\source\vss\data\rights.dat" denied
Tue Feb 03 12:47:53 PST 2004 - PDC (10.10.10.29) - User "two" disconnected

The windows user DOES have rights to the whole data directory where the
rights.dat file is located, he can even writ to this directory (including
this file). 

This does not happen with the other user?

Please help. I am completely lost on this one.

Thanks

Alex Dearden
Hitachi Printing Solutions America
IT Department